1. Field of the Invention
The present invention relates generally to ink cartridges. In particular, the present invention is directed towards ink cartridges which may be used in combination with ink jet printers.
2. Description of Related Art
A known printer may be configured to detect when an amount of ink within an ink cartridge is relatively low. For example, a known ink cartridge may comprise a float which floats on the ink within the ink cartridge, and a known printer may comprise an optical sensor positioned on the bottom side of the ink cartridge. When there is a sufficient amount of ink within the ink cartridge, the float is positioned above the optical sensor, and the light of the optical sensor is not blocked by the float. Nevertheless, as the ink within the ink cartridge is consumed by the printer, the surface of the ink within the ink cartridge moves downwards, which causes the float to also move downwards. When the surface of the ink moves down to a predetermined level, the light from the optical sensor is blocked by the float, and the printer determines that there is an insufficient amount of ink within the ink cartridge.
Another known ink cartridge may be installed in a printer from the horizontal direction. This known ink cartridge comprises an ink supply outlet for supplying ink externally, which is positioned on the front surface of the ink cartridge in the insertion direction of the ink cartridge into the printer. A communication path is provided in the ink cartridge and connected to the ink supply outlet. The communication path is connected to the printer by the insertion operation of the ink cartridge from the horizontal direction. The communication path extends in parallel to the insertion direction. Because this ink cartridge is inserted into the printer in the horizontal direction, there is no need to provide access from the upper side of the printer when the ink cartridge is replaced. Therefore, the space on the upper side of the printer may be effectively used. It may be possible to overlay devices vertically.